/*******************************************************************************
 * ============LICENSE_START====================================================
 * * org.onap.aai
 * * ===========================================================================
 * * Copyright © 2017 AT&T Intellectual Property. All rights reserved.
 * * Copyright © 2017 Amdocs
 * * ===========================================================================
 * * Licensed under the Apache License, Version 2.0 (the "License");
 * * you may not use this file except in compliance with the License.
 * * You may obtain a copy of the License at
 * * 
 *  *      http://www.apache.org/licenses/LICENSE-2.0
 * * 
 *  * Unless required by applicable law or agreed to in writing, software
 * * distributed under the License is distributed on an "AS IS" BASIS,
 * * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * * See the License for the specific language governing permissions and
 * * limitations under the License.
 * * ============LICENSE_END====================================================
 * *
 * * ECOMP is a trademark and service mark of AT&T Intellectual Property.
 * *
 ******************************************************************************/
package com.att.cadi.lur;

import java.security.Principal;
import java.util.List;

import com.att.cadi.CachingLur;
import com.att.cadi.CadiException;
import com.att.cadi.CredVal;
import com.att.cadi.Lur;
import com.att.cadi.Permission;

/**
 * EpiLUR
 * 
 * Short for "Epic LUR". Be able to run through a series of LURs to obtain the validation needed.
 * 
 * The pun is better for the other pattern... "TAF" (aka EpiTaf), but it's still the larger picture of 
 * LURs that will be accomplished.
 * 
 * FYI, the reason we separate LURs, rather than combine, is that Various User Repository Resources have
 * different Caching requirements.  For instance, the Local User Repo (with stand alone names), never expire, but might be
 * refreshed with a change in Configuration File, while the Remote Service based LURs will need to expire at prescribed intervals 
 * 
 *
 */
public final class EpiLur implements Lur {
	private final Lur[] lurs;
	
	/**
	 * EpiLur constructor
	 * 
	 * Construct the EpiLur from variable TAF parameters
	 * @param lurs
	 * @throws CadiException
	 */
	public EpiLur(Lur ... lurs) throws CadiException{
		this.lurs = lurs;
		if(lurs.length==0) throw new CadiException("Need at least one Lur implementation in constructor");
	}

	public boolean fish(Principal bait, Permission pond) {
		if(pond==null) {
			return false;
		}
		boolean rv = false;
		Lur lur;
		for(int i=0;!rv && i<lurs.length;++i) {
			rv = (lur = lurs[i]).fish(bait, pond);
			if(!rv && lur.handlesExclusively(pond)) break;
		}
		return rv;
	}

	public void fishAll(Principal bait, List<Permission> permissions) {
		for(Lur lur : lurs) {
			lur.fishAll(bait, permissions);
		}
	}

	public void destroy() {
		for(Lur lur : lurs) {
			lur.destroy();
		}
	}

	/**
	 * Return the first Lur (if any) which also implements UserPass 
	 * @return
	 */
	public CredVal getUserPassImpl() {
		for(Lur lur : lurs) {
			if(lur instanceof CredVal) {
				return (CredVal)lur;
			}
		}
		return null;
	}

	// Never needed... Only EpiLur uses...
	public boolean handlesExclusively(Permission pond) {
		return false;
	}
	
	/**
	 * Get Lur for index.  Returns null if out of range
	 * @param idx
	 * @return
	 */
	public Lur get(int idx) {
		if(idx>=0 && idx<lurs.length) {
			return lurs[idx];
		}
		return null;
	}

	public boolean supports(String userName) {
		for(Lur l : lurs) {
			if(l.supports(userName))return true;
		}
		return false;
	}

	public void remove(String id) {
		for(Lur l : lurs) {
			if(l instanceof CachingLur) {
				((CachingLur<?>)l).remove(id);
			}
		}
	}
	
	public Lur subLur(Class<? extends Lur> cls ) {
		for(Lur l : lurs) {
			if(l.getClass().isAssignableFrom(cls)) {
				return l;
			}
		}
		return null;
	}

	@Override
	public Permission createPerm(String p) {
		return new LocalPermission(p);
	}

	/* (non-Javadoc)
	 * @see com.att.cadi.Lur#clear(java.security.Principal, java.lang.StringBuilder)
	 */
	@Override
	public void clear(Principal p, StringBuilder report) {
		for(Lur lur : lurs) {
			lur.clear(p, report);
		}
	}
	
	public String toString() {
		StringBuilder sb = new StringBuilder();
		for(Lur lur : lurs) {
			sb.append(lur.getClass().getSimpleName());
			sb.append(": Report\n");
			sb.append(lur.toString());
			sb.append('\n');
		}
		return sb.toString();
	}
}